I hate sentences like this. I can understand it but they really make it a challenge by writing like that. In my opinion it is poor writing because it forces your mind to think hard about how to parse it. Why couldn't they break it up like this to male it easier to understand? As modern concepts of negligence developed, two things became embedded in both medicine and law. One was the emphasis of litigation to deter substandard behavior. The other was individual accountability for procedures and actions casually linked to adverse outcomes.

adverbial phrase: As modern concepts of negligence developed noun phrase (the subject of the sentence): [the act of] emphasizing litigation to deter substandard behavior and individual accountability for procedures and actions causally linked to adverse outcomes verb + object of the verb: became embedded in both medicine and law. It means that there are too many lawyers in the world.